engine SSANGYONG NEW ACTYON SPORTS 2012 Repair Manual

03-14
(6) Low Pressure System Pressure Test
Inspection procedure ▶
All wirings/connectors and fuel lines should
be connected and the engine should work
properly.
Prepare a special tool for low pressure test
and clean it thoroughly to prevent foreign
materials from entering. 1.
2.
Disconnect the key connector for fuel filter connection, and connect both connectors to the
fuel filter and hose. 3.
Start the engine and check visually for clogged low pressure fuel system, excessive air or air
entry.
If the fuel flow is not sufficient or air is in the fuel, repair the leak area. 4.
5.

03-152210-01
Static test for backleak of injector ▶
Disconnect the injector return hose and cover
the openings with caps shaped screw
(included in the special tool). 1.
Connect the hose of the container for
measuring backleak to the return nipple of
the injector.
(prevent air entry to the low pressure line) 2.
Disconnect the IMV connector of the
high pressure pump and then fuel
pressure sensor connector. 3.
The connector of the injector can be easily
contaminated. Always keep it clean.
Crank the engine 2 times for 5 seconds.
Check the time for flow if injector backleak
and confirm that it is within the specified
range. 4.
5.
If the value is out of the specified range,
replace the injector.
SpecificationBelow 20 sec.

03-16
Dynamic test for backleak of injector ▶
Warm up the engine so that the engine
coolant temperature be over 80℃ and star
the engine again.
Disconnect the injector return hose and
cover the openings with caps shaped
screw (included in the special tool).. 1.
2.
Connect the hose of the container for
measuring backleak to the return nipple of
the injector.
Start the engine again and let the engine
idle for 30 seconds.
Perform backleak test of fuel system with a
diagnostic device after 30 seconds. 3.
4.
5.
This test consists of 4 cycles, and the engine
rpm reaches 3,500 rpm for 18 seconds in each
cycle.
Check the amount of backleak collected
into the container and confirm that it is
within the specified range. 6.
Specification38 ml or less

03-172210-01
HP pump pressure test ▶
Prepare a special tool for high pressure
test and clean it thoroughly to prevent
foreign materials from entering. 1.
Disconnect the high pressure fuel supply
pipe on the HP pump and install the close
rail in the tool kit. 2.
Connect the other end of the close rail to
the fuel rail for test. 3.
Disconnect the return hose for HP pump
and connect the clear hose and connect
its the other end to the return port of the
fuel rail for test. 4.
Connect the digital tester connector to the
sensor connector of the fuel rail for test.
Crank the engine 2 times for 5 seconds after
removing the IMV connector and fuel rail
pressure sensor connector.
Read the pressure value displayed on the
tester display is within the specified 5.
6.
7.
Specification1,050 bar or more

03-18
3. CAUTIONS FOR DI ENGINE
1) Cautions for DI Engine
This chapter describes the cautions for DI engine equipped vehicle. This includes the water
separation from engine, warning lights, symptoms when engine malfunctioning, causes and
actions.
DI Engine 1.
Comparatively conventional diesel engines, DI engine controls the fuel injection and timing
electrically, delivers high power and reduces less emission..
System Safety Mode 2.
When a severe failure has been occurred in a vehicle, the system safety mode is activated to
protect the system. It reduces the driving force, restricts the engine speed (rpm) and stops
engine operation. Refer to "Diagnosis" section in this manual.
Engine CHECK Warning Lamp 3.
The Engine CHECK warning lamp on the instrument cluster comes on when the
fuel or major electronic systems of the engine are not working properly. As a result,
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95008c00470094008800a00047009a009b0088009300930055>
Water Separator Warning Lamp 4.
When the water level inside water separator in fuel filter exceeds a certain level
(approx. 45 cc), this warning light comes on and buzzer sounds.
Also, the driving force of the vehicle decreases (torque reduction). If these
conditions occur, immediately drain the water from fuel filter.

03-192210-01
2) Cleanness
(1) Cleanness of DI engine fuel system
Cleanness of DI engine fuel system and service procedures ▶
The fuel system for DI engine consists of transfer (low pressure) line and high pressure line.
Its highest pressure reaches over 1,800 bar.
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preciseness.
The pressure regulation and injector operation are done by electric source from engine ECU.
Accordingly, if the internal valve is stuck due to foreign materials, injector remains open.
Even in this case, the HP pump still operates to supply high pressurized fuel. This increases the
pressure to combustion chamber (over 250 bar) and may cause fatal damage to engine.
You can compare the thickness of injector nozzle hole and hair as shown in below figure (left
side). The below figure shows the clearance between internal operating elements.
The core elements of fuel system has very high preciseness that is easily affected by dust or very
small foreign material. Therefore, make sure to keep the preliminary works and job procedures in
next pages. If not, lots of system problems and claims may arise.
Hair
Nozzle holeValve actuator lift - 0.028 mm
Diameter
0.04 mm
Operating
clearance
0.002 mm
Diameter
2.0 mm

03-20
(2) Di engine and its expected problems and remedies can be caused by
water in fuel
System supplement against paraffin separation ▶
In case of Diesel fuel, paraffin, one of the elements, can be separated from fuel during winter and
then can stick on the fuel filter blocking fuel flow and causing difficult starting finally. Oil
companies supply summer fuel and winter fuel by differentiating mixing ratio of kerosene and
other elements by region and season. However, above phenomenon can be happened if stations
have poor facilities or sell improper fuel for the season. In case of DI engine, purity of fuel is very
important factor to keep internal preciseness of HP pump and injector.
Accordingly, more dense mesh than conventional fuel filter is used. To prevent fuel filter internal
clogging due to paraffin separation, SYMC is using fuel line that high pressure and temperature
fuel injected by injector returns through fuel filter to have an effect of built-in heater (see fuel
system).
System supplement and remedy against water in fuel ▶
As mentioned above, some gas stations supply fuel with excessive than specified water. In the
conventional IDI engine, excessive water in the fuel only causes dropping engine power or engine
hunting. However, fuel system in the DI engine consists of precise components so water in the
fuel can cause malfunctions of HP pump due to poor lubrication of pump caused by poor coating
film during high speed pumping and bacterization (under long period parking). To prevent
problems can be caused by excessive water in fuel, water separator is installed inside of fuel
filter. When fuel is passing filter, water that has relatively bigger specific gravity is accumulated on
the bottom of the filter.
Water drain from water separator ▶
If water in the separator on the fuel filter exceeds a certain level, it will be supplied to HP pump
with fuel, so the engine ECU turns on warning lamp on the meter cluster and buzzer if water level
is higher than a certain level.
Due to engine layout, a customer cannot easily drain water from fuel filter directly, so if a
customer checks in to change engine oil, be sure to perform water drain from fuel filter.
Water
separator
To separate the water from the fuel filter,
remove the fuel filter assembly first.

03-212210-01
1. OVERVIEW
The components in fuel system supply the fuel and generate the high pressure to inject the fuel to
each injector. They are controlled by the engine ECU.
The common rail fuel injection system consists of fuel tank, fuel line, low pressure line which
supplies low pressure fuel to the low pressure pump (including high pressure pump), common rail
which distributes and accumulates the high pressurized fuel from the fuel pump, high pressure
line which connected to the injector, and the engine control unit (ECU) which calculates the
accelerator pedal position and controls the overall performance of vehicle based on the input
signals from various sensors.
1) Fuel Flow Diagram

03-22
2. SYSTEM LAYOUT AND OPERATION
1) Layout
For sensor and actuator control logic, refer to Chapter "Engine Control".
Engine ECU (D20DTR)
Engine control by various
signalsFuel tank
Fuel metering by sender
HFM sensor
Measuring intake air mass
and temperature
Crankshaft position sensor
Measuring engine rpmInjector (C3I)
Pre-injection, main injection,
after-injection by signals from
ECUCamshaft position sensor
Determining injection order

03-232210-01
Accelerator pedal position
sensor
Detecting driver's intention
for speed up/down
Fuel rail assembly
Relieving the pulsation.
Measuring the fuel pressure.
Distributing the fuel to injectors.
Fuel filter assembly
Supplying clean fuel/fuel
heating/water separation by
priming pump
Plunger type HP pump (1,800 bar)
Vane type LP pump (6 bar)
T-MAP sensor
Measuring booster pressure
and temperature
High pressure pump
Generating high pressurized fuel
and supplying it according to
engine rpm, required volume,
required pressure